Genesis 25:30
He said to Jacob, "Let me eat some of that red stew, for I am famished." (That is why he was also called Edom.)

Genesis 25:32
"Look," said Esau, "I am about to die, so what good is a birthright to me?"

Deuteronomy 21:16
when that man assigns his inheritance to his sons he must not appoint the son of the beloved wife as the firstborn over the son of the unloved wife.

Deuteronomy 21:17
Instead, he must acknowledge the firstborn, the son of his unloved wife, by giving him a double portion of all that he has. For that son is the firstfruits of his father's strength; the right of the firstborn belongs to him.

1 Chronicles 5:1
These were the sons of Reuben the firstborn of Israel. Though he was the firstborn, his birthright was given to the sons of Joseph son of Israel, because Reuben defiled his father's bed. So he is not reckoned according to birthright.

1 Chronicles 5:2
And though Judah prevailed over his brothers and a ruler came from him, the birthright belonged to Joseph.